body {
    text-align: center;
}

.box {
    width: 200px;
    height: 200px;
    border: 10px solid black;
    margin: 20px auto;
}

.col {
    float: left;
    width: 10px;
}

.middle {
    float: left;
    width: 180px;
    height: 180px;
    line-height: 180px;
    text-align: center;
    font-size: x-large;
    color: blue;
}

.clear {
    clear: both;
}

.brick {
    float: left;
    width: 10px;
    height: 10px;
}

.black {
    background-color: black;
}

.white {
    background-color: white;
}

button {
    margin: 10px;
}